In the July-Dec 2024 reporting period we completed the following activities:

Project 1: Monitoring and Evaluation of a New Saturated Waterway Conservation Practice • Installed N sensors for real-time monitoring of Clark Porter’s grassed waterway • Bi-weekly sampling of monitoring wells at Clark Porter’s grassed waterway

Project 2: Quantifying Stacked Conservation Practices for Reducing Nutrient Losses at a Field Scale • Installed new saturated buffer at Mike Paustian's • Instrumented new saturated buffer with live nitrate, turbidity, and flow sensors Read more about Quantifying Nutrient Load Reduction Practices at Multiple Field Sites Jan 2025

The second year of monthly (4-week interval) sampling of the study field is underway. A consistent grid of 100 samples per month is being taken from the field to a depth of 15 cm (6 inches), packed into individual bags, and sent for further analysis at a commercial laboratory for soil nutrients. Digital maps are being created using two approaches, spatial autocorrelation (ordinary kriging) and spatial association (machine learning (ML) with random forest). For the ML method, the covariates are fed into the training process with 80% of the sample results. Read more about Spatial models for scaling optimal nutrient management research from plot to field and watershed scales Sep 2025

All relevant datasets from the study watershed (Walnut Creek) have been retrieved and organized. Analysis has been completed for the first part of this project, which summarizes the impact of Neal Smith National Wildlife Refuge on downstream nitrate and sediment over the past 30 years.

Work has also begun on the second part of this project, which explores orthophosphate transport using a unique, high-resolution dataset produced by the USDA  Agricultural Research Service.

Other accomplishments and activities Read more about Investigating Long-term Nutrient Trends and Short-term Orthophosphate Dynamics in a HUC12 Basin with Extensive Land Use Change Sep 2025

During the second half of 2024, several significant rain events occurred at both study sites. Real-time flow through each inlet and real-time nitrate data continued to be collected. However, the later part of 2024 mimicked 2023 and drought conditions returned to the study sites. Still, valuable data was collected in the spring that was sufficient to answer the study questions proposed. Read more about Evaluating the effectiveness of stacked practices: Utilizing modified blind inlets at terrace sites for N and P load reductions Sep 2025